Recently, there have rapidly been increased the number of patients suffering from allergic symptoms (hereunder referred to as “pollinosis”) accompanied by, for instance, conjunctivitis (itching and congestion of eyes), rhinitis (sneezing, snivel and nasal congestion) and bronchial asthma, which are caused due to the allergic hypersensitivity against pollens of, for instance, hinoki (white cedar), sugi (Japanese cedar) and ragweed (Ambrosia artemisiifolia), and dead bodies of, for instance, ticks or mites. In respect of pollinosis, a steroidal drug has been used for alleviating the related symptoms, but the symptoms have never been alleviated in a large number of patients even if such a steroidal drug is administered to these patients. Accordingly, there has been desired for the development of an effective means for treating and/or alleviating pollinosis.